The cfg subpackage builds a control flow graph of ast.Nodes.
The lostcancel module checks this graph to find paths, from a call to
WithCancel to a return statement, on which the cancel variable is
not used. (A trivial case is simply assigning the cancel result to
the blank identifier.)
In a sample of 50,000 source files, the new check found 2068 blank
assignments and 118 return-before-cancel errors. I manually inspected
20 of the latter and didn't find a single false positive among them.
Change-Id: I84cd49445f9f8d04908b04881eb1496a96611205
Reviewed-on: https://go-review.googlesource.com/24150
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
- Simplified the code.
- Removed types for slice aliases from composite literals' whitelist, since they
are properly handled by vet.
Fixes#15408
Updates #9171
Updates #11041
Change-Id: Ia1806c9eb3f327c09d2e28da4ffdb233b5a159b0
Reviewed-on: https://go-review.googlesource.com/22318
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
This excludes internal and testdata packages, as well as func types.
No new whitelist entries were found.
Change-Id: Ie7d42ce0a235394e4bcabf09e155726a35cd2d3d
Reviewed-on: https://go-review.googlesource.com/21822
Reviewed-by: Rob Pike <r@golang.org>
This was a mistake made when bringing cmd/vet into the main repo.
Fixes#13416.
Change-Id: I03b512ab944577c56085aea06df8ff5e1acc16d7
Reviewed-on: https://go-review.googlesource.com/17455
Reviewed-by: Matthew Dempsky <mdempsky@google.com>